Composite materials and composite building elements based on EP(D)M are conventional. Normally, they comprise three layers:
1. a layer based on EP(D)M; this layer is resistant to heat and ozone and exhibits swelling (solvent) resistance against polar, organic media;
2. a layer based on an elastomer component imparting to this layer a particular, desired property, for example, flame retardance or swelling (solvent) resistance against nonpolar, organic media; and
3. an intermediate layer based on an elastomer component having good capability for covulcanization with EP(D)M, on the one hand, and the elastomer component of the other layer, on the other hand, or a fabric interlayer.
The composite materials and composite construction elements of the prior art, although having a satisfactorily strong interlayer bond obtained by vulcanization welding, are cumbersome in their manufacture and thus expensive. This is primarily because of the requirement of the intermediate layer.